uk.ac.gla.terrier.structures.indexing.singlepass
Class BlockPostingInRun

java.lang.Object
  uk.ac.gla.terrier.structures.indexing.singlepass.PostingInRun
      uk.ac.gla.terrier.structures.indexing.singlepass.SimplePostingInRun
          uk.ac.gla.terrier.structures.indexing.singlepass.BlockPostingInRun

Direct Known Subclasses:

BlockFieldPostingInRun

public class BlockPostingInRun
extends SimplePostingInRun

Class holding the information for a posting list read from a previously written run at disk. Used in the merging phase of the Single pass inversion method. This class knows how to append itself to a BitOut and it represents a posting with blocks information (tf, df, [docid, idf, blockFr [blockid]])

Author:

Roi Blanco

Constructor Summary

BlockPostingInRun()
Constructor for the class.

Method Summary

int	append(BitOut bos, int last, int runShift) Writes the document data of this posting to a BitOut It encodes the data with the right compression methods.

Methods inherited from class uk.ac.gla.terrier.structures.indexing.singlepass.PostingInRun

append, getDf, getTerm, getTF, setDf, setPostingSource, setTerm, setTF

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BlockPostingInRun

public BlockPostingInRun()

Constructor for the class.

Method Detail

append

public int append(BitOut bos,
                  int last,
                  int runShift)
           throws java.io.IOException

Writes the document data of this posting to a BitOut It encodes the data with the right compression methods. The stream is written as d1, idf(d1), blockNo(d1), bid1, bid2, ..., d2 - d1, idf(d2), blockNo(d2), ... etc

Overrides:

append in class SimplePostingInRun

Parameters:

bos - BitOut to be written.

last - int representing the last document written in this posting.

runShift - amount of delta to apply to the first posting read.

Returns:

The last posting written.

Throws:

java.io.IOException